1. Field of the Invention
The present invention relates to a rotation member unit, such as a photoconductive member, etc., capable of rotating and a drive introduction member secured to at least one end of the rotation member, and in particular to a reusable rotation member unit and an image forming apparatus employing the rotation member.
2. Discussion of the Background Arts
It is known that a rotation member unit includes a rotation member, such as a roller member, etc., and a drive introduction member secured to one end of the rotation member for introducing rotational driving force from a drive transmission member, such as a motor gear, etc., to the rotation member. Especially, an electro-photographic image forming apparatus usually mounts this type of rotation member unit. For example, a photoconductive member unit, which includes a drum shaped photoconductive member, a flange secured to at least one end of the photoconductive member, and a drive introduction gear or a drive introduction coupling integrally arranged with the flange.
In such a rotation member unit, when the drive introduction gear or the drive introduction coupling deteriorates due to wear or the like, the drive introduction member is replaced and the rotation member unit, such as a process cartridge, etc., can be reused as a recycling product.
However, the flange is generally secured to the rotation member firmly by means of engagement, riveting, or adhesion or the like so as not to run idle in relation to the rotation member.
In such a configuration, when a drive introduction member needs to be replaced, since the flange is not easily detached, recycling of the rotation member unit needs a lot of labor or increases cost.
Then, a coupling is inserted or attached to a flange firmly secured to one end of a drum shaped photoconductive member in a rotation axis direction as described in the Japanese Patent Application Laid Open No. 2002-311756. A heat expansion coefficient of such a flange and a coupling is different from each other. Thus, these members can be readily separated by cooling and largely shrinking one of the flange and the coupling in relation to the other.
Further, as described in the Japanese Patent Application Laid Open No. 2004-101825, a photoconductive member unit includes a hole between a flange inserted with a gear into one end of a photoconductive member in an axis direction and an internal periphery of the photoconductive member, and fluid is inserted and injected through the hole. Such a gear flange forming a drive introduction gear and serves as a drive introduction member is either adhered to the inner periphery of the photoconductive member or pressure inserted into the photoconductive member via an elastic member. Thus, when the fluid (or powder) is injected through the hole between the photoconductive member inner periphery and an insertion position to which the gear flange is inserted, the photoconductive member and the gear flange adhering to each other can be readily separated. Otherwise, the gear flange pressure inserted into the photoconductive member can be readily separated from the photoconductive member by deformation of the elastic member caused by injection of the liquid (or powder).
Further, as described in the Japanese Patent Application Laid Open No. 2005-140919, a photoconductive member unit includes an engagement section for engaging a particular kind of separation use jig on a gear flange inserted or adhered to one end of a photoconductive member in a direction of a rotation axis. In such a configuration, the gear flange can be readily withdrawn from the photoconductive member using the separation use jig. However, in anyone of the above-mentioned photoconductive member units, when the coupling is withdrawn from the flange, or the gear flange is withdrawn from the photoconductive member, strong pressure needs to be applied to the photoconductive member via a holding section, and accordingly, the photoconductive member is possibly cut or damaged. Because, the photoconductive member is firmly held.
Especially, the photoconductive member of the Japanese Patent Application Laid Open No. 2005-140919 tends to be cut, because the large pressure is applied to a holding section of the photoconductive member when a gear flange is forcibly withdrawn from the photoconductive member by the separation use jig, because the gear flange is adhered to the photoconductive member by adhesion.
Further, the photoconductive member unit of the Japanese Patent Application Laid Open No. 2002-311756 needs expensive equipment due to necessity of a cooling device for cooling the flange or the coupling. Further, labor, and accordingly, a cost increase, because the flange or the coupling needs to be cooled until a sufficient shrinking effect is obtained.
Further, the photoconductive member unit of the Japanese Patent Application Laid Open No. 2004-101825 needs the injection device equipment therefore and is expensive.